Diversity, habitats and size-frequency distribution of the gastropod genus Conus at Dahab in the gulf of Aqaba, Northern Red Sea.

Autor(en)

Sarah Zauner, Martin Zuschin

Abstrakt

Topographically complex subtidal reefs of the Indo-West Pacific region are characterised
by a high species richness of cone snails of the genus Conus (up to 36 on
some reefs) but low population densities (≤1 individual/m2), whereas Conus assemblages
on reef flats usually support fewer species (5-9) and high population densities
(up to 5.2 individuals/m2). Subtidal sand areas are known to be least species-rich (1-6
species). Although the diversity of this predatory gastropod genus has been described
previously from different areas of the Indo-Pacific, little ecological information is
available on Conus in the Northern Red Sea. Therefore, data from five habitat types
were obtained along 73 line-transects (245 m2), which yielded ecological data for a
total of 175 individuals of 9 species. In accordance with former findings, our results
demonstrate that the reef flat was the habitat with the highest observed population
densities (6.15 individuals/m2) but low species diversity (H’ = 0.9; 5 species); subtidal
reefs, in contrast, were characterised by low densities (0.13 individuals/m2) and
a relatively high species diversity (H ’= 1.5; 6 species). This suggests that Conus diversity
and species richness in the Northern Red Sea around Dahab is lower than in
other parts of the Indo-West Pacific region. Furthermore, hard- and soft substrata
were dominated by different Conus species in accordance to the distribution of favourable
microhabitat patches, the degree of physical stress and the availability of
refuges and prey organisms. The fact that these Conus were predominantly smallbodied
vermivores (size range: 6-85 mm; mean shell size: 15 mm; SD = 9 mm) suggests
that this size class possesses an advantage over molluscivores and piscivores.
Except for subtidal reefs, which showed a highly variable species composition, the
studied habitat types around Dahab were characterised by distinct assemblages of
Conus.
Keywords: Northern Red Sea; Southern Gulf of Aqaba; Conus; size-frequency distribution;
species diversity;

Organisation(en)

Institut für Paläontologie

Journal

Zoology in the Middle East

Band

62

Seiten

125-136

Anzahl der Seiten

12

ISSN

0939-7140

DOI

https://doi.org/10.1080/09397140.2016.1182781

Publikationsdatum

2016

Peer-reviewed

Ja

ÖFOS 2012

105118 Paläontologie

Schlagwörter

ASJC Scopus Sachgebiete

Animal Science and Zoology

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/diversity-habitats-and-sizefrequency-distribution-of-the-gastropod-genus-conus-at-dahab-in-the-gulf-of-aqaba-northern-red-sea(198869d0-e8e4-4ec7-859a-676bedfcdb61).html